llvm-mirror/lib/CodeGen/MachineRegionInfo.cpp
Reid Kleckner 68092989f3 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00

150 lines
4.8 KiB
C++

//===- lib/Codegen/MachineRegionInfo.cpp ----------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineRegionInfo.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/RegionInfoImpl.h"
#include "llvm/CodeGen/MachinePostDominators.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#define DEBUG_TYPE "machine-region-info"
using namespace llvm;
STATISTIC(numMachineRegions, "The # of machine regions");
STATISTIC(numMachineSimpleRegions, "The # of simple machine regions");
namespace llvm {
template class RegionBase<RegionTraits<MachineFunction>>;
template class RegionNodeBase<RegionTraits<MachineFunction>>;
template class RegionInfoBase<RegionTraits<MachineFunction>>;
} // end namespace llvm
//===----------------------------------------------------------------------===//
// MachineRegion implementation
MachineRegion::MachineRegion(MachineBasicBlock *Entry, MachineBasicBlock *Exit,
MachineRegionInfo* RI,
MachineDominatorTree *DT, MachineRegion *Parent) :
RegionBase<RegionTraits<MachineFunction>>(Entry, Exit, RI, DT, Parent) {}
MachineRegion::~MachineRegion() = default;
//===----------------------------------------------------------------------===//
// MachineRegionInfo implementation
MachineRegionInfo::MachineRegionInfo() = default;
MachineRegionInfo::~MachineRegionInfo() = default;
void MachineRegionInfo::updateStatistics(MachineRegion *R) {
++numMachineRegions;
// TODO: Slow. Should only be enabled if -stats is used.
if (R->isSimple())
++numMachineSimpleRegions;
}
void MachineRegionInfo::recalculate(MachineFunction &F,
MachineDominatorTree *DT_,
MachinePostDominatorTree *PDT_,
MachineDominanceFrontier *DF_) {
DT = DT_;
PDT = PDT_;
DF = DF_;
MachineBasicBlock *Entry = GraphTraits<MachineFunction*>::getEntryNode(&F);
TopLevelRegion = new MachineRegion(Entry, nullptr, this, DT, nullptr);
updateStatistics(TopLevelRegion);
calculate(F);
}
//===----------------------------------------------------------------------===//
// MachineRegionInfoPass implementation
//
MachineRegionInfoPass::MachineRegionInfoPass() : MachineFunctionPass(ID) {
initializeMachineRegionInfoPassPass(*PassRegistry::getPassRegistry());
}
MachineRegionInfoPass::~MachineRegionInfoPass() = default;
bool MachineRegionInfoPass::runOnMachineFunction(MachineFunction &F) {
releaseMemory();
auto DT = &getAnalysis<MachineDominatorTree>();
auto PDT = &getAnalysis<MachinePostDominatorTree>();
auto DF = &getAnalysis<MachineDominanceFrontier>();
RI.recalculate(F, DT, PDT, DF);
LLVM_DEBUG(RI.dump());
return false;
}
void MachineRegionInfoPass::releaseMemory() {
RI.releaseMemory();
}
void MachineRegionInfoPass::verifyAnalysis() const {
// Only do verification when user wants to, otherwise this expensive check
// will be invoked by PMDataManager::verifyPreservedAnalysis when
// a regionpass (marked PreservedAll) finish.
if (MachineRegionInfo::VerifyRegionInfo)
RI.verifyAnalysis();
}
void MachineRegionInfoPass::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<MachineDominatorTree>();
AU.addRequired<MachinePostDominatorTree>();
AU.addRequired<MachineDominanceFrontier>();
MachineFunctionPass::getAnalysisUsage(AU);
}
void MachineRegionInfoPass::print(raw_ostream &OS, const Module *) const {
RI.print(OS);
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MachineRegionInfoPass::dump() const {
RI.dump();
}
#endif
char MachineRegionInfoPass::ID = 0;
char &MachineRegionInfoPassID = MachineRegionInfoPass::ID;
INITIALIZE_PASS_BEGIN(MachineRegionInfoPass, DEBUG_TYPE,
"Detect single entry single exit regions", true, true)
INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
INITIALIZE_PASS_DEPENDENCY(MachinePostDominatorTree)
INITIALIZE_PASS_DEPENDENCY(MachineDominanceFrontier)
INITIALIZE_PASS_END(MachineRegionInfoPass, DEBUG_TYPE,
"Detect single entry single exit regions", true, true)
// Create methods available outside of this file, to use them
// "include/llvm/LinkAllPasses.h". Otherwise the pass would be deleted by
// the link time optimization.
namespace llvm {
FunctionPass *createMachineRegionInfoPass() {
return new MachineRegionInfoPass();
}
} // end namespace llvm